TM 5-1940-321-13&P
NOTE:
Use a shop pressure gauge, P/N 7111, rather than the pressure gauge supplied
in the repair kit.
( 1 ) Check the keel pressure and buoyancy tube pressure as described in
paragraph 5-7. Correct as necessary. If the craft has been deflated or partially
deflated for more than one hour, wait one hour and recheck the pressures as
described in paragraph 5-7.
NOTE:
The correct pressure for the buoyancy tubes is 240-280 mb (3.5 to 4.1 psi). Do
not lean on or place nay weight on the craft during pressure measurement.
NOTE:
The correct pressure for the keel is 220-240 mb (3.2-3.5 psi). Do not lean on or
place any weight on the craft during pressure measurement.
( 2 ) Record the exact buoyancy tube and keel pressures at start of test in the space
provided in the upper section of each test data sheet. Also enter the test start
date, time, and temperature data.
( 3 ) Tighten all valve caps firmly by hand.
NOTE:
Do not change pressure gauges during air pressure test. Use the same gauge.
( 4 ) Wait 24 hours and recheck pressures. Do not touch any valves or add or
release air during this period. Do not sit or lean on the craft or place objects on
the craft during pressure readings.
( 5 ) Remove the isolator clamps from the lower buoyancy tube inflation hoses.
Remove the metal valve cap from one of the intercommunicating valves, and
using the same pressure gauge used in previous steps, firmly insert the gauge
into the valve opening.
( 6 ) On page 1 of the test data sheets ( figure 5-22), record the exact buoyancy
tube pressure at the end of the test. Also record the end-of-test date, time, and
ambient temperature.
5-35
